CN113272472A

CN113272472A - Distance measurement between gas distribution device and substrate support at high temperature

Info

Publication number: CN113272472A
Application number: CN201980087971.5A
Authority: CN
Inventors: 马克·E·爱默生; 尼克·雷·小莱恩巴格
Original assignee: Lam Research Corp
Current assignee: Lam Research Corp
Priority date: 2019-01-03
Filing date: 2019-12-27
Publication date: 2021-08-17
Anticipated expiration: 2039-12-27
Also published as: CN118792641A; TWI853873B; TW202040100A; KR20250030004A; KR20210100193A; KR102773015B1; US12050112B2; US20220364858A1; US20200217657A1; TW202500952A; US11408734B2; CN113272472B; WO2020142367A1

Abstract

A substrate processing system comprising: a laser triangulation sensor configured to transmit and receive light through a window of an outer wall of the substrate processing chamber. The controller is configured to: positioning the laser triangulation sensor such that the laser triangulation sensor transmits light onto a measurement feature disposed between a first surface of a substrate support and a second surface of a gas distribution device, wherein the second surface faces the first surface; and determining a first distance between the first surface and the second surface based on a difference between: a second distance between the laser triangulation sensor and the first surface measured using the laser triangulation sensor; and a third distance between the laser triangulation sensor and the second surface measured using the laser triangulation sensor.

Description

Distance measurement between gas distribution device and substrate support at high temperature

Cross Reference to Related Applications

This application claims priority from U.S. patent application No.16/238,891, filed on 3/1/2019. The above-referenced application is incorporated by reference herein in its entirety.

Technical Field

The present disclosure relates to substrate processing chambers, and more particularly, to systems and methods for measuring a distance between a gas distribution device and a substrate support.

Background

The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.

Substrate processing systems may be used to process substrates such as semiconductor wafers. Exemplary processes that may be performed on the substrate include, but are not limited to, Chemical Vapor Deposition (CVD), Atomic Layer Deposition (ALD), conductor etching, and/or other etching, deposition, or cleaning processes. The substrate may be disposed on a substrate support, such as a pedestal, an electrostatic chuck (ESC), or the like, in a process chamber of a substrate processing system.

The substrate support may comprise a ceramic layer arranged to support a substrate. For example, the wafer may be electrostatically clamped to the ceramic layer during processing.

Disclosure of Invention

In one feature, a substrate processing system includes: a laser triangulation sensor configured to transmit and receive light through a window of an outer wall of the substrate processing chamber. The controller is configured to: positioning the laser triangulation sensor such that the laser triangulation sensor transmits light onto a measurement feature disposed between a first surface of a substrate support and a second surface of a gas distribution device, wherein the second surface faces the first surface; and determining a first distance between the first surface and the second surface based on a difference between: a second distance between the laser triangulation sensor and the first surface measured using the laser triangulation sensor; and a third distance between the laser triangulation sensor and the second surface measured using the laser triangulation sensor.

In other features, the measurement feature is configured to: reflecting light from the laser triangulation sensor onto a first surface of the substrate support while the laser triangulation sensor outputs light onto the first surface of the measurement feature; and reflecting light from the laser triangulation sensor onto a second surface of the gas distribution device when the laser triangulation sensor outputs light onto the second surface of the measurement feature.

In other features, the measurement feature comprises a knife-edge prism comprising a mirror coating.

In other features, the controller is configured to increase a temperature within the substrate processing chamber to greater than or equal to a predetermined processing temperature, wherein the controller is configured to position the laser triangulation sensor when the temperature is greater than or equal to the predetermined processing temperature.

In other features, the predetermined processing temperature is at least 80 ℃.

In other features, an adjustment mechanism is configured to raise and lower a portion of the gas distribution device.

In other features, the controller is configured to selectively actuate the adjustment mechanism based on the first distance.

In other features, the controller is configured to selectively actuate the adjustment mechanism to adjust the first distance toward a first target distance.

In other features, the controller is further configured to: positioning the laser triangulation sensor such that the laser triangulation sensor transmits light to a second measurement feature disposed between the first surface of the substrate support and the second surface of the gas distribution device; and determining a fourth distance between the first surface and the second surface based on a second difference between: a fifth distance between the laser triangulation sensor and the first surface measured using the laser triangulation sensor; and a sixth distance between the laser triangulation sensor and the second surface measured using the laser triangulation sensor.

In other features, the controller is further configured to: positioning the laser triangulation sensor such that the laser triangulation sensor transmits light to a third measurement feature disposed between the first surface of the substrate support and the second surface of the gas distribution device; and determining a seventh distance between the first surface and the second surface based on a third difference between: an eighth distance between the laser triangulation sensor and the first surface measured using the laser triangulation sensor; and a ninth distance between the laser triangulation sensor and the second surface measured using the laser triangulation sensor.

In other features, a first adjustment mechanism is configured to raise and lower a first point on the gas distribution device; a second adjustment mechanism configured to raise and lower a second point on the gas distribution device independent of the first adjustment mechanism; a third adjustment mechanism configured to raise and lower a third point on the gas distribution apparatus independent of the first and second adjustment mechanisms.

In other features, the controller is configured to selectively actuate at least one of the first, second, and third adjustment mechanisms based on at least one of the first, second, and third distances.

In one feature, a method of processing a substrate includes: transmitting and receiving light through a window of an outer wall of the substrate processing chamber by a laser triangulation sensor; positioning the laser triangulation sensor such that the laser triangulation sensor transmits light onto a measurement feature disposed between a first surface of a substrate support and a second surface of a gas distribution device, wherein the second surface faces the first surface; determining a first distance between the first surface and the second surface based on a difference between the following two when the laser triangulation sensor transmits light onto the measurement feature: a second distance between the laser triangulation sensor and the first surface measured using the laser triangulation sensor; and a third distance between the laser triangulation sensor and the second surface measured using the laser triangulation sensor.

In other features, the substrate processing method further comprises, with the measurement feature: reflecting light from the laser triangulation sensor onto a first surface of the substrate support while the laser triangulation sensor outputs light onto the first surface of the measurement feature; and reflecting light from the laser triangulation sensor onto a second surface of the gas distribution device when the laser triangulation sensor outputs light onto the second surface of the measurement feature.

In other features, the substrate processing method further comprises increasing a temperature within the substrate processing chamber to greater than or equal to a predetermined processing temperature, wherein the positioning comprises: and when the temperature is greater than or equal to the preset processing temperature, positioning the laser triangular sensor.

In other features, the predetermined processing temperature is at least 80 ℃.

In other features, the substrate processing method further comprises: raising and lowering a portion of the gas distribution device.

In other features, the raising and lowering includes at least one of raising and lowering the portion of the gas distribution device based on the first distance.

In other features, the raising and lowering includes at least one of raising and lowering the portion of the gas distribution device to adjust the first distance toward a first target distance.

In other features, the substrate processing method further comprises: positioning the laser triangulation sensor such that the laser triangulation sensor transmits light to a second measurement feature disposed between the first surface of the substrate support and the second surface of the gas distribution device; and determining a fourth distance between the first surface and the second surface based on a second difference between: a fifth distance between the laser triangulation sensor and the first surface measured using the laser triangulation sensor; and a sixth distance between the laser triangulation sensor and the second surface measured using the laser triangulation sensor.

In other features, the substrate processing method further comprises: positioning the laser triangulation sensor such that the laser triangulation sensor transmits light to a third measurement feature disposed between the first surface of the substrate support and the second surface of the gas distribution device; and determining a seventh distance between the first surface and the second surface based on a third difference between: an eighth distance between the laser triangulation sensor and the first surface measured using the laser triangulation sensor; and a ninth distance between the laser triangulation sensor and the second surface measured using the laser triangulation sensor.

In other features, the substrate processing method further comprises: raising and lowering a first point on the gas distribution device; raising and lowering a second point on the gas distribution device independently of the first point; raising and lowering a third point on the gas distribution device independently of the first point and the second point.

In other features, the method of processing a substrate further comprises at least one of raising and lowering at least one of the first, second, and third points based on at least one of the first, second, and third distances.

Further scope of applicability of the present disclosure will become apparent from the detailed description, claims and drawings. The detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

Drawings

The present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein:

FIG. 1 is a functional block diagram of an example of a substrate processing system including an elevatable and lowerable gas distribution apparatus;

FIG. 2 is an exemplary embodiment of a raisable, lowerable and tiltable gas distribution apparatus;

3A-3D contain illustrations of examples of raisable, lowerable and tiltable gas distribution apparatus in various orientations;

FIG. 4 is an exemplary orientation control system;

FIG. 5 is a diagram of an exemplary measurement substrate;

FIG. 6 is a side view of an exemplary embodiment of a measurement feature;

FIG. 7 is a side view of an exemplary distance measurement system;

FIG. 8A is an exemplary diagram of providing light over a leading edge of a measurement feature;

FIG. 8B includes an exemplary illustration of providing light below the leading edge of a measurement feature;

9A-9C include exemplary diagrams providing light to different measurement features; and

FIG. 10 contains a flow chart depicting an example method of determining a distance between a gas distribution device and a substrate support at a location of a measurement feature.

In the drawings, reference numerals may be repeated among the figures to indicate like and/or identical elements.

Detailed Description

A substrate support, such as an electrostatic chuck, supports a substrate in a substrate processing chamber. The substrate is disposed on a substrate support during processing. Examples of processes that may be performed on a substrate include, but are not limited to, deposition (e.g., Chemical Vapor Deposition (CVD), Atomic Layer Deposition (ALD), plasma enhanced CVD (pecvd), plasma enhanced ALD (peald), etc.), etching, and cleaning.

A gas distribution device, such as a showerhead, distributes gas within the substrate processing chamber. Different processes may utilize different target orientations of the gas distribution device relative to the substrate support or relative to a substrate disposed on the substrate support. Different parts of the process may also utilize different target orientations.

The plurality of adjustment mechanisms may be configured to adjust an orientation of the gas distribution device. The controller may actuate the adjustment mechanism to achieve a target orientation of the gas distribution device.

Although not processing within the substrate processing chamber, one or more sensors may be used within the processing chamber to measure the orientation of the gas distribution apparatus. However, these sensors are not suitable for measuring the orientation of the gas distribution apparatus during processing because the temperature rating of the sensor is less than the temperature within the substrate processing chamber during processing.

The orientation of the gas distribution device during processing is different from the orientation when no processing is performed. This may be due to, for example, different components having different coefficients of thermal expansion and/or bending of one or more components during processing.

According to the present disclosure, a distance sensor (e.g., a laser triangulation sensor) measures the distance between the gas distribution device and the substrate support when the temperature within the process chamber is greater than or equal to a predetermined process temperature (e.g., 80 ℃ C. or greater). Based on the distance, the adjustment mechanism can be adjusted to achieve a target orientation of the gas distribution apparatus during processing. This can increase the accuracy of processing and the resulting substrate.

Referring now to fig. 1, an example of a substrate processing system 100 including a substrate support 104 is shown. The substrate support 104 is disposed within a process chamber 108. During processing of the substrate 112, the substrate 112 is disposed on the substrate support 104. The substrates are loaded into the process chamber 108 and unloaded from the process chamber 108 through one or more doors, such as door 116.

The gas delivery system 120 includes gas sources 122-1, 122-2, …, and 122-N (collectively referred to as gas sources 122) connected to valves 124-1, 124-2, …, and 124-N (collectively referred to as valves 124) and mass flow controllers 126-1, 126-2, …, and 126-N (collectively referred to as MFCs 126). The MFC 126 controls the flow of gas from the gas source 122 to a manifold 128 for the mixed gas.

The output of manifold 128 is supplied to manifold 136 via optional pressure regulator 132. The output of the manifold 136 is then input to a gas distribution device 140, such as a showerhead. A gas distribution device 140 distributes gas within the process chamber 108. Although

manifolds

128 and 136 are shown, a single manifold may be used. The manifold 136 may be integrated within a gas distribution device 140. The configuration of the gas distribution device 140 is configured to be vertically adjustable and tiltable, as described in more detail below.

In some examples, the resistive heater 160 may be used to control the temperature of the substrate support 104 (and thus the temperature of the substrate 112). The substrate support 104 may contain a coolant channel 164. Cooling fluid from a fluid reservoir 168 and a pump 170 may be supplied to the coolant channels 164. The cooling fluid may cool the substrate support (and thus the substrate 112).

Pressure sensors

172 and 174 may be disposed in manifold 128 or manifold 136, respectively, and measure pressure. The valve 178 and the pump 180 may exhaust gases from the process chamber 108 and/or control the pressure within the process chamber 108.

The controller 182 controls the delivery of gases from the gas delivery system 120 to the process chamber 108, for example, via the gas distribution device 140. The controller 182 uses the valve 178 and the pump 180 to control the pressure in the process chamber and/or the exhaust of the reactants. The controller 182 controls the temperature of the substrate support 104 and the substrate 112 based on temperature feedback, for example from sensors (not shown) within the substrate support 104 and/or sensors (not shown) that measure the temperature of the coolant.

The controller 182 also controls the orientation of the gas distribution device 140. More specifically, the controller 182 controls the raising and lowering of the gas distribution device 140 to achieve a target distance between the gas distribution device 140 and the substrate support 104.

A transparent window 190 is disposed in a wall of the process chamber 108. As discussed further below, the distance sensor 194 measures the distance between the gas distribution device 140 and the substrate support 104 at a plurality of different locations when the process chamber is heated to at least a predetermined process temperature. The predetermined process chamber may be at, for example, 80 degrees celsius or higher. The actuator 198 actuates the distance sensor 194 to measure distance, as discussed further below.

Referring now to FIG. 2, a perspective view of an exemplary embodiment of a gas distribution device (e.g., showerhead) 140 is provided. For example, the gas distribution device 140 may correspond to a three degree of freedom (DOF) adjustable showerhead.

The gas distribution device 140 includes a stem portion 204 and a plasma-facing gas distribution plate (e.g., faceplate) 208. The stem 204 is connected to the upper surface of the process chamber 108 via a collar 212. For example, collar 212 may include an upper plate 216 and a lower plate 220. The upper plate 216 is fixedly attached to the upper surface of the process chamber 108. In some examples, the upper surface of the process chamber 108 may be used as the upper plate 216. The process gas is provided to the gas distribution plate 208 through the inlet 224 via the stem portion 204.

The stem portion 204 is connected to a lower plate 220, and the lower plate 220 is tiltable, raisable, and lowerable relative to the upper plate 216. For example, gas distribution apparatus 140 may include adjustment mechanisms 228-1, 228-2, and 228-3 (collectively, "adjustment mechanisms 228"). For example, the adjustment mechanism 228 may correspond to a screw, a linear actuator, or other suitable type of actuator. In the screw example, adjusting the screw tilts, raises, or lowers the gas distribution device 140, thereby changing the plane of the substrate-facing surface of the gas distribution device 140. For example, turning a screw may cause the distance between various portions of the upper plate 216 and the lower plate 220 to increase and decrease, thereby causing the stem 204 and the gas distribution plate 208 to move accordingly. Although an example of three adjustment mechanisms is provided, the gas distribution apparatus 140 may include more than three adjustment mechanisms.

Fig. 3A-3D include exemplary illustrations of gas distribution apparatus 140 in different positions relative to substrate support 104. In fig. 3A, the gas distribution device 140 is shown in a non-tilted position, wherein the plane of the substrate-facing surface of the gas distribution device 140 is parallel to the plane of the top surface of the substrate support 104. In fig. 3A, the adjustment mechanism 228 may be adjusted such that the gas distribution device 140 is at a maximum distance from the substrate support 104. Conversely, in fig. 3B, the adjustment mechanism 228 may be adjusted such that the gas distribution device 140 is at a minimum distance from the substrate support 104. In fig. 3B, the gas distribution device 140 is shown in a non-tilted position, wherein the plane of the substrate-facing surface of the gas distribution device 140 is parallel to the plane of the top surface of the substrate support 104.

The tilted position of the gas distribution device 140 is shown in fig. 3C and 3D, for example, in which the plane of the substrate-facing surface of the gas distribution device 140 is not parallel to the plane of the top surface of the substrate support 104. Although an example is provided herein in which the gas distribution apparatus 140 is located above the substrate support 104, the gas distribution apparatus 140 may also be located below the substrate support 104.

FIG. 4 contains a functional block diagram of an exemplary position control system. The target controller 404 may be configured to determine a target distance between the gas distribution device 140 and the substrate support 104. For example, the target controller 404 may be configured to determine a first target distance between the gas distribution device 140 and the substrate support 104 at the position of the adjustment mechanism 228-1. The target controller 404 may also determine a second target distance between the gas distribution device 140 and the substrate support 104 at the position of the adjustment mechanism 228-2. The target controller 404 may also determine a third target distance between the gas distribution device 140 and the substrate support 104 at the position of the adjustment mechanism 228-3.

In various embodiments, the first, second, and third target distances may be predetermined fixed values and may be stored in memory 408. Alternatively, the first, second, and third target distances may be floating and may be selected, for example, by the target controller 404 for the processing performed. Based on the processing performed, the target controller 404 may select a set of first, second, and third target distances from the memory 408. As another option for the target distance, a target relationship between the plane of the substrate-facing surface of the gas distribution device 140 and the plane of the top surface of the substrate support 104 may be used.

The temperature controller 409 controls the heating and cooling of the process chamber 108. For example, the temperature controller 409 may control heating by the heater 160 and cooling by a cooling system including the pump 170.

When the temperature controller 409 has heated the process chamber 108 such that the temperature within the process chamber 108 is greater than or equal to the predetermined process temperature, the distance sensor 194 measures a first distance between the gas distribution device 140 and the substrate support 104 at the first position. The distance sensor 194 also measures a second distance between the gas distribution device 140 and the substrate support 104 at the second position during a time when the temperature within the process chamber 108 is greater than or equal to the predetermined process temperature. The distance sensor 194 also measures a third distance between the gas distribution device 140 and the substrate support 104 at a third position during a time when the temperature within the process chamber 108 is greater than or equal to the predetermined process temperature. The predetermined process temperature is calibratable and may be, for example, greater than or equal to 80 degrees celsius.

The measurement controller 410 determines the first, second, and third distances based on measurements from the distance sensor 194, as discussed further below. The actuation controller 412 may selectively actuate the actuators 416-1, 416-2, and 416-3 (collectively "actuators 416"), which in turn actuate the adjustment mechanism 228.

The actuation controller 412 may actuate the actuator 416-1 to adjust the first distance (measured using the distance sensor 194) to the first target distance. The actuation controller 412 may actuate the actuator 416-2 to adjust the second distance (measured using the distance sensor 194) to the second target distance. The actuation controller 412 may actuate the actuator 416-3 to adjust the third distance (measured using the distance sensor 194) to the third target distance.

In examples of the adjustment mechanism 228 that include a screw, the actuator 416 may include a rotary actuator configured to rotate the adjustment mechanism 228, respectively. Alternatively, in examples of the adjustment mechanism 228 that include a pin or another type of linear actuator, the actuator 416 may include a linear actuator configured to linearly actuate the adjustment mechanism 228 up and down. However, the actuator 416 may be another type of actuator.

In various embodiments, actuator 416 may be omitted. The target controller 404 may display the first, second, and third target distances on a user interface 420 (e.g., a display). The target controller 404 may also display the first, second, and third distances measured using the distance sensor 194 on a user interface 420 (e.g., a display). The user may manually actuate the adjustment mechanism 228 based on information provided on the user interface 420.

The distance sensor 194 may measure the first, second, and third distances between the gas distribution device 140 and the substrate support 104 using a measurement substrate. Fig. 5 contains an exemplary illustration of a measurement substrate 504.

The measurement substrate 504 includes first, second, and third measurement features 508-1, 508-2, and 508-3 (collectively, "measurement features 508") at locations corresponding to the first, second, and third locations, respectively. The spacing between the measurement features 508 may be such that the measurement features 508 may be positioned (vertically) directly below the adjustment mechanism 228, respectively. The controller 182 may control the robot to load the measurement substrate 504 onto the substrate support 104 such that the measurement features 508 are each located vertically below the adjustment mechanism 228. Alternatively, the measurement substrate 504 may be manually loaded onto the substrate support 104.

The first, second, and third measurement features 508 may be located on (e.g., adhered to) an upper surface of the measurement substrate 504 or embedded in the measurement substrate 504, for example. In various embodiments, the measurement feature 508 may be embedded within the measurement substrate 504 such that the measurement feature 508 reflects light through the measurement substrate 504 and to the substrate support 104.

Fig. 6 includes a side view of an exemplary embodiment of a first measurement feature 508-1. The second and third measured characteristics 508-2 and 508-3 may be the same as the first measured characteristic 508-1. The first, second, and third measurement features 508 may comprise knife-edge prisms having a mirror coating on their outer surfaces. The mirror coating is reflective up to a predetermined distance and up to a predetermined temperature. The predetermined distance may be, for example, 650 nanometers (nm) or another suitable distance. The predetermined temperature may be, for example, 650 degrees celsius or another suitable temperature. For example, the mirror coating may comprise sapphire or other suitable material. The dimensions of the exemplary embodiment may be 8 millimeters (mm) in height, 10mm in thickness, 12.5mm in length, and 45 degrees in angle (θ), although other dimensions and shapes may be used. The exemplary illustrations may or may not be to scale. Although one example is provided, the first, second, and third measurement features 508-1, 508-2, and 508-3 may have different shapes and/or sizes.

When the plane of the substrate-facing surface of the gas distribution device 140 and the plane of the top surface of the substrate support 104 are parallel, the first, second, and third measurement features 508 are configured to reflect light in a direction perpendicular to the plane of the substrate-facing surface of the gas distribution device 140 and the plane of the top surface of the substrate support 104. For example, the first measurement feature 508-1 includes a first reflective surface 604 and a second reflective surface 608. The first reflective surface 604 reflects the received light towards the gas distribution device 140. The second reflective surface 608 reflects light toward the substrate support 104.

FIG. 7 contains a side view of an exemplary distance measurement system. For simplicity, only a portion of the gas distribution plate 208, the substrate support 104, and the metrology substrate 504 are shown in FIG. 7.

The distance sensor 194 may comprise, for example, a laser triangulation sensor. For example only, the distance sensor 194 may be a Keyence laser triangulation sensor model LK-G502, a Keyence laser triangulation sensor model LK-G507, or another suitable triangulation sensor or another optical distance or displacement sensor. The distance sensor 194 may have a measurement resolution of less than one micron (μm), a measurement repeatability of less than 12.7 μm-3 σ, and a probe (light) spot size (e.g., diameter) of less than 1mm over a distance of 1000 mm. Although example features are provided, the distance sensor 194 may have other suitable features.

The actuator 198 actuates the distance sensor 194 to measure the first, second, and third distances. The actuator 198 is configured to raise and lower the distance sensor 194 and rotate the distance sensor 194. Controller 182, such as position controller 704, controls actuator 198 and, thus, the positioning of distance sensor 194.

For example, the distance sensor 194 may be mounted on the board 712. The actuator 198 may rotate the plate 712 via the shaft 716 to rotate the distance sensor 194. Actuator 198 may raise and lower plate 712 to raise and lower distance sensor 194. In various embodiments, the first actuator may raise and lower the distance sensor 194, and the second actuator may rotate the distance sensor 194.

The distance sensor 194 includes a light source 720, such as a solid state laser light source (e.g., a laser diode). The light source 720 outputs light (e.g., a laser beam) in a predetermined direction. In various embodiments, the light source 720 may output light through the first lens 724.

Rotation of the distance sensor 194 causes the light output by the light source 720 to scan left and right (rotationally). The up and down movement of the distance sensor 194 causes the light output by the light source 720 to scan vertically up and down.

The distance sensor 194 also includes a detector 728 that outputs a distance between the distance sensor 194 and an object that receives light output by the light source 720 based on light reflected back to the distance sensor 194. More specifically, detector 728 generates the distance based on the location at which light is reflected from the object back onto detector 728. The detector 728 may include, for example, a Complementary Metal Oxide Semiconductor (CMOS) detector, a Charge Coupled Device (CCD) detector, a Position Sensitive Diode (PSD) detector, or another suitable type of detector. In various embodiments, the reflected light may be provided onto detector 728 via second lens 732. The output light and the reflected light may travel through a window 190 of the process chamber 108.

To determine the first distance, the position controller 704 rotates the distance sensor 194 to output light to the first measurement feature 508-1. The position controller 704 may rotate the distance sensor 194 such that the distance sensor 194 outputs light in a direction perpendicular (orthogonal) to a plane that extends vertically (perpendicularly) from the leading edge 736 of the first measurement feature 508-1. The position controller 704 also raises or lowers the distance sensor 194 so that the distance sensor 194 outputs light to one of: over the leading edge 736; and below the leading edge 736. After raising or lowering the distance sensor 194 to output light one of above the leading edge 736 and below the leading edge 736, the position controller 704 raises or lowers the distance sensor 194 so that the distance sensor 194 outputs light to the other of above the leading edge 736 and below the leading edge 736.

Fig. 8A includes an exemplary illustration of providing light over the leading edge 736. Fig. 8B includes an exemplary illustration of providing light below the leading edge 736.

As light is output over the leading edge 736, the first measurement feature 508-1 reflects the light upward, and the distance sensor 194 then measures the upward distance between the distance sensor 194 and the substrate-facing surface of the gas distribution device 140. When the light is output below the leading edge 736, the first measurement feature 508-1 reflects the light downward, and the distance sensor 194 then measures the downward distance between the distance sensor 194 and the top surface of the measurement substrate 504 or substrate support 104. If the measurement feature 508 is disposed directly on the substrate support 104 or reflects light through the measurement substrate 504, the measurement feature 508 reflects light downward as the light is output below the leading edge 736, and the distance sensor 194 then measures the downward distance between the distance sensor 194 and the top surface of the substrate support 104.

The measurement controller 410 receives the determined upward and downward distances at the first measurement feature 508-1 from the distance sensor 194. The measurement controller 410 determines the first distance based on the difference between the upward distance and the downward distance. For example, measurement controller 410 may set the first distance to be the upward distance minus the downward distance.

Before or after positioning the distance sensor 194 to determine the first distance, the position controller 704 also determines a second distance using the second measurement feature 508-2 and a third distance using the third measurement feature 508-3. The position controller 704 determines the first, second and third distances in any order. In the same manner as taken for the first measurement feature 508-1, the position controller 704 moves the distance sensor 194 to output light to the second and third measurement features 508-2 and 508-3 to determine the second and third distances, respectively. This includes rotating the distance sensor 194 to each of the second and third measurement features 508-2 and 508-3 and raising and lowering the distance sensor 194 to output light above and below the leading edges of the second and third measurement features 508-2 and 508-3.

Fig. 9A includes an exemplary top view of rotating the distance sensor 194 to face the first measurement feature 508-1 to measure the first distance. Fig. 9B includes an exemplary top view of rotating the distance sensor 194 to face the second measurement feature 508-2 to measure the second distance. Fig. 9C includes an exemplary top view of rotating the distance sensor 194 to face the third measurement feature 508-3 to measure the third distance.

Fig. 10 contains a flow chart describing an exemplary method of determining the first, second, and third distances and adjusting the gas distribution device 140 to the first, second, and third target distances. Control begins when the metrology feature 508 is disposed on the substrate support 104 within the process chamber 108. The measurement feature 508 may be positioned directly on the substrate support 104 or on or within the measurement substrate 504.

At 1004, the temperature controller 409 heats the process chamber 108 (e.g., by applying power to the heater 160) such that the temperature within the process chamber 108 is greater than or equal to a predetermined process temperature (e.g., 80 degrees celsius). The temperature controller 409 maintains the temperature at or above the predetermined process temperature until the control is over.

At 1008, the position controller 704 actuates the actuator 198 to direct the light output by the distance sensor 194 at the first measurement feature 508-1. This includes aiming the light output by the distance sensor 194 above the leading edge of the first measurement feature 508-1 at the first time and aiming the light output by the distance sensor 194 below the leading edge 736 of the first measurement feature 508-1 at the second time. The distance sensor 194 measures a first upward distance when the light output by the distance sensor 194 is directed over the leading edge 736 of the first measurement feature 508-1. The distance sensor 194 measures a first downward distance when the light output by the distance sensor 194 is directed below the leading edge 736 of the first measurement feature 508-1. Position controller 704 actuates actuator 198 to rotate distance sensor 194 and raise and lower distance sensor 194.

At 1012, the measurement controller 410 determines a first distance between the substrate-facing surface of the gas distribution device 140 and the substrate support 104 (or the measurement substrate 504) based on a difference between the first upward distance and the first downward distance. For example, the measurement controller 410 may set the first distance to be based on or equal to the first upward distance minus the first downward distance.

At 1016, the position controller 704 actuates the actuator 198 to direct the light output by the distance sensor 194 at the second measurement feature 508-2. This includes aiming the light output by the distance sensor 194 above the leading edge of the second measurement feature 508-2 at the third time and aiming the light output by the distance sensor 194 below the leading edge of the second measurement feature 508-2 at the fourth time. The distance sensor 194 measures a second upward distance when the light output by the distance sensor 194 is directed over the leading edge of the second measurement feature 508-2. The distance sensor 194 measures a second downward distance when the light output by the distance sensor 194 is directed below the leading edge 736 of the second measurement feature 508-2. Position controller 704 actuates actuator 198 to rotate distance sensor 194 and raise and lower distance sensor 194.

At 1020, the measurement controller 410 determines a second distance between the substrate-facing surface of the gas distribution device 140 and the substrate support 104 (or the measurement substrate 504) based on a difference between the second upward distance and the second downward distance. For example, the measurement controller 410 may set the second distance to be based on or equal to the second upward distance minus the second downward distance.

At 1024, the position controller 704 actuates the actuator 198 to direct light output by the distance sensor 194 at the third measurement feature 508-3. This includes aiming the light output by the distance sensor 194 above the leading edge of the third measurement feature 508-3 at the fifth time and aiming the light output by the distance sensor 194 below the leading edge of the third measurement feature 508-3 at the sixth time. The distance sensor 194 measures a third upward distance when the light output by the distance sensor 194 is directed over the leading edge of the third measurement feature 508-3. The distance sensor 194 measures a third downward distance when the light output by the distance sensor 194 is directed below the leading edge of the third measurement feature 508-3. Position controller 704 actuates actuator 198 to rotate distance sensor 194 and raise and lower distance sensor 194.

At 1028, the measurement controller 410 determines a third distance between the substrate-facing surface of the gas distribution device 140 and the substrate support 104 (or the measurement substrate 504) based on a difference between the third upward distance and the third downward distance. For example, the measurement controller 410 may set the third distance to be based on or equal to the third upward distance minus the third downward distance.

At 1032, the actuation controller 412 may determine whether the first, second, and third ranges all fall within predetermined amounts of the first, second, and third target ranges, respectively. The predetermined amount may be calibrated and may be, for example, 1 μm or less. If 1032 is a negative result, at 1036, the actuation controller 412 may adjust one or more adjustment mechanisms 228 to adjust the first, second, and third distances to fall within predetermined amounts of the first, second, and third target distances, respectively. Control may return to 1008. If 1032, the result is yes, control may end.

In various embodiments, 1032 may be omitted. The first, second, and third distances and the first, second, and third target distances may be displayed on the user interface 420. The user may manually adjust one or more adjustment mechanisms 228 to adjust and bring the first, second, and third distances within a predetermined amount of the first, second, and third target distances, respectively.

The foregoing description is merely illustrative in nature and is in no way intended to limit the disclosure, its application, or uses. The broad teachings of the disclosure can be implemented in a variety of forms. Therefore, while this disclosure includes particular examples, the true scope of the disclosure should not be so limited since other modifications will become apparent upon a study of the drawings, the specification, and the following claims. It should be understood that one or more steps of the method may be performed in a different order (or simultaneously) without altering the principles of the present disclosure. Furthermore, while each embodiment is described above as having certain features, any one or more of those features described with respect to any embodiment of the present disclosure may be implemented in and/or combined with the features of any other embodiment, even if the combination is not explicitly described. In other words, the described embodiments are not mutually exclusive, and substitutions of one or more embodiments with one another remain within the scope of the present disclosure.

Various terms are used to describe spatial and functional relationships between elements (e.g., between modules, circuit elements, between semiconductor layers, etc.), including "connected," joined, "" coupled, "" adjacent, "" immediately adjacent, "" on top, "" above, "" below, "and" disposed. Unless a relationship between first and second elements is explicitly described as "direct", when such a relationship is described in the above disclosure, the relationship may be a direct relationship, in which no other intermediate elements are present between the first and second elements, but may also be an indirect relationship, in which one or more intermediate elements are present (spatially or functionally) between the first and second elements. As used herein, the phrase "at least one of A, B and C" should be interpreted to mean logic (a OR B OR C) using a non-exclusive logic OR (OR), and should not be interpreted to mean "at least one of a, at least one of B, and at least one of C".

In some embodiments, the controller is part of a system, which may be part of the above examples. Such systems may include semiconductor processing equipment including one or more processing tools, one or more chambers, one or more platforms for processing, and/or specific processing components (wafer susceptors, gas flow systems, etc.). These systems may be integrated with electronics for controlling the operation of semiconductor wafers or substrates before, during, and after their processing. The electronic device may be referred to as a "controller," which may control various components or subcomponents of one or more systems. Depending on the process requirements and/or type of system, the controller can be programmed to control any of the processes disclosed herein, including the delivery of process gases, temperature settings (e.g., heating and/or cooling), pressure settings, vacuum settings, power settings, Radio Frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and operation settings, wafer transfer in and out of tools and other transfer tools, and/or load locks connected or interfaced with specific systems.

In general terms, a controller may be defined as an electronic device having various integrated circuits, logic, memory, and/or software to receive instructions, issue instructions, control operations, enable cleaning operations, enable endpoint measurements, and the like. An integrated circuit may include a chip in firmware that stores program instructions, a Digital Signal Processor (DSP), a chip defined as an Application Specific Integrated Circuit (ASIC), and/or one or more microprocessors or microcontrollers that execute program instructions (e.g., software). The program instructions may be instructions that are sent to the controller in the form of various individual settings (or program files) that define operating parameters for performing specific processes on or for a semiconductor wafer or system. In some embodiments, the operating parameters may be part of a recipe defined by a process engineer to complete one or more process steps during fabrication of one or more layer(s), material, metal, oxide, silicon dioxide, surface, circuitry, and/or die of a wafer.

In some embodiments, the controller may be part of or coupled to a computer that is integrated with, coupled to, otherwise networked to, or a combination of the systems. For example, the controller may be in the "cloud" or all or part of a fab (fab) host system, which may allow remote access to wafer processing. The computer may implement remote access to the system to monitor the current progress of the manufacturing operation, check the history of past manufacturing operations, check trends or performance criteria for multiple manufacturing operations, change parameters of the current process, set processing steps to follow the current process, or begin a new process. In some examples, a remote computer (e.g., a server) may provide the process recipe to the system over a network (which may include a local network or the Internet). The remote computer may include a user interface that enables parameters and/or settings to be entered or programmed and then transmitted from the remote computer to the system. In some examples, the controller receives instructions in the form of data specifying parameters for each process step to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process to be performed and the type of tool with which the controller is configured to interface or control. Thus, as noted above, the controllers can be distributed, for example, by including one or more discrete controllers networked together and operating toward a common purpose (e.g., processing and control as described herein). An example of a distributed controller for such purposes is one or more integrated circuits on a room that communicate with one or more integrated circuits that are remote (e.g., at the platform level or as part of a remote computer), which combine to control processing on the room.

Example systems can include, but are not limited to, a plasma etch chamber or module, a deposition chamber or module, a spin rinse chamber or module, a metal plating chamber or module, a cleaning chamber or module, a bevel edge etch chamber or module, a Physical Vapor Deposition (PVD) chamber or module, a Chemical Vapor Deposition (CVD) chamber or module, an Atomic Layer Deposition (ALD) chamber or module, an Atomic Layer Etch (ALE) chamber or module, an ion implantation chamber or module, a track chamber or module, and any other semiconductor processing system that can be associated with or used in the manufacture and/or preparation of semiconductor wafers.

As described above, depending on the process step or steps to be performed by the tool, the controller may communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, neighboring tools, tools located throughout the factory, a host computer, another controller, or a tool used in the material transport that transports wafer containers to and from tool locations and/or load ports in a semiconductor manufacturing facility.

Claims

1. A substrate processing system, comprising:

a distance sensor configured to transmit and receive light through a window of an outer wall of the substrate processing chamber;

a controller configured to:

positioning the distance sensor such that the distance sensor transmits light onto a measurement feature disposed between a first surface of a substrate support and a second surface of a gas distribution device,

wherein the second surface faces the first surface; and

determining a first distance between the first surface and the second surface based on a difference between:

a second distance between the distance sensor and the first surface measured using the distance sensor; and

a third distance between the distance sensor and the second surface measured using the distance sensor.

2. The substrate processing system of claim 1, wherein the measurement feature is configured to:

reflecting light from the distance sensor onto a first surface of the substrate support when the distance sensor outputs light onto the first surface of the measurement feature; and

reflecting light from the distance sensor onto a second surface of the gas distribution device when the distance sensor outputs light onto the second surface of the measurement feature.

3. The substrate processing system of claim 1, wherein the measurement feature comprises a knife-edge prism comprising a mirror coating.

4. The substrate processing system of claim 1, wherein the controller is configured to increase a temperature within the substrate processing chamber to greater than or equal to a predetermined processing temperature,

wherein the controller is configured to position the distance sensor when the temperature is greater than or equal to the predetermined processing temperature.

5. The substrate processing system of claim 4, wherein the predetermined processing temperature is at least 80 ℃.

6. The substrate processing system of claim 1, further comprising:

an adjustment mechanism configured to raise and lower a portion of the gas distribution device.

7. The substrate processing system of claim 6, wherein the controller is configured to selectively actuate the adjustment mechanism based on the first distance.

8. The substrate processing system of claim 7, wherein the controller is configured to selectively actuate the adjustment mechanism to adjust the first distance toward a first target distance.

9. The substrate processing system of claim 1, wherein the controller is further configured to:

positioning the distance sensor such that the distance sensor transmits light to a second measurement feature disposed between the first surface of the substrate support and the second surface of the gas distribution device; and

determining a fourth distance between the first surface and the second surface based on a second difference between:

a fifth distance between the distance sensor and the first surface measured using the distance sensor; and

a sixth distance between the distance sensor and the second surface measured using the distance sensor.

10. The substrate processing system of claim 9, wherein the controller is further configured to:

positioning the distance sensor such that the distance sensor transmits light to a third measurement feature disposed between the first surface of the substrate support and the second surface of the gas distribution device; and

determining a seventh distance between the first surface and the second surface based on a third difference between:

an eighth distance between the distance sensor and the first surface measured using the distance sensor; and

a ninth distance between the distance sensor and the second surface measured using the distance sensor.

11. The substrate processing system of claim 10, further comprising:

a first adjustment mechanism configured to raise and lower a first point on the gas distribution device;

a second adjustment mechanism configured to raise and lower a second point on the gas distribution device independent of the first adjustment mechanism;

a third adjustment mechanism configured to raise and lower a third point on the gas distribution apparatus independent of the first and second adjustment mechanisms.

12. The substrate processing system of claim 11, wherein the controller is configured to selectively actuate at least one of the first, second, and third adjustment mechanisms based on at least one of the first, second, and third distances.

13. A method of substrate processing, comprising:

transmitting and receiving light through a window of an outer wall of the substrate processing chamber by a distance sensor;

wherein the second surface faces the first surface;

14. The method of substrate processing according to claim 13, further comprising, by the measurement feature:

15. The substrate processing method of claim 13, wherein the measurement feature comprises a knife-edge prism comprising a mirror coating.

16. The method of claim 13, further comprising increasing a temperature within the substrate processing chamber to greater than or equal to a predetermined processing temperature,

wherein the positioning includes: positioning the distance sensor when the temperature is greater than or equal to the predetermined process temperature.

17. The substrate processing method of claim 16, wherein the predetermined processing temperature is at least 80 ℃.

18. The method of claim 13, further comprising raising and lowering a portion of the gas distribution apparatus.

19. The method of claim 18, wherein the raising and lowering includes at least one of raising and lowering the portion of the gas distribution device based on the first distance.

20. The substrate processing method of claim 19, wherein the raising and lowering includes at least one of raising and lowering the portion of the gas distribution device to adjust the first distance toward a first target distance.

21. The method of processing a substrate of claim 13, further comprising:

22. The method of processing a substrate of claim 21, further comprising:

23. The method of processing a substrate of claim 22, further comprising:

raising and lowering a first point on the gas distribution device;

raising and lowering a second point on the gas distribution device independently of the first point;

raising and lowering a third point on the gas distribution device independently of the first point and the second point.

24. The method of claim 23, further comprising at least one of raising and lowering at least one of the first, second, and third points based on at least one of the first, second, and third distances.